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Definitions |
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sw register_source, RAM_destination
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#store word in source register into RAM destination
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li register_destination, value
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#load immediate value into destination register
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lw register_destination, RAM_source
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#copy word (4 bytes) at source RAM location to destination register.
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mflo $t1
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# move quantity in special register Lo to $t1: $t1 = Lo # used to get at result of product or quotient
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sb register_source, RAM_destination
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#store byte (low-order) in source register into RAM destination
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b target
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# unconditional branch to program label target
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addi $t2,$t3, 5
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# $t2 = $t3 + 5; "add immediate" (no sub immediate)
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bgt $t0,$t1,target
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# branch to target if $t0 > $t1
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j target
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# unconditional jump to program label target
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ble $t0,$t1,target
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# branch to target if $t0
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lw $t2, 4($t0)
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* load word at RAM address ($t0+4) into register $t2 * "4" gives offset from address in register $t0
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jr $ra
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# "jump register" * jump to return address in $ra (stored by jal instruction)
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sw $t2, -12($t0)
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* store word in register $t2 into RAM at address ($t0 - 12) * negative offsets are fine
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add $t0,$t1,$t2
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# $t0 = $t1 + $t2; add as signed (2's complement) integers
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jr $t3
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# jump to address contained in $t3 ("jump register")
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bge $t0,$t1,target
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# branch to target if $t0 >= $t1
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sub $t2,$t3,$t4
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# $t2 = $t3 - $t4
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blt $t0,$t1,target
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# branch to target if $t0
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la $t0, var1
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copy RAM address of var1 (presumably a label defined in the program) into register $t0
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div $t5,$t6
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# Lo = $t5 / $t6 (integer quotient) # Hi = $t5 mod $t6 (remainder)
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bne $t0,$t1,target
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# branch to target if $t0 $t1
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beq $t0,$t1,target
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# branch to target if $t0 = $t1
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lb register_destination, RAM_source
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#copy byte at source RAM location to low-order byte of destination register,# and sign-e.g.tend to higher-order bytes
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subu $t1,$t6,$t7
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# $t1 = $t6 - $t7; subtract as unsigned integers
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sw $t2, ($t0)
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store word in register $t2 into RAM at address contained in $t0
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mfhi $t0
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# move quantity in special register Hi to $t0: $t0 = Hi
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jal sub_label
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# "jump and link" * copy program counter (return address) to register $ra (return address register) * jump to program statement at sub_label
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lw $t2, ($t0)
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load word at RAM address contained in $t0 into $t2
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mult $t3,$t4
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# multiply 32-bit quantities in $t3 and $t4, and store 64-bit # result in special registers Lo and Hi: (Hi,Lo) = $t3 * $t4
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addu $t1,$t6,$t7
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# $t1 = $t6 + $t7; add as unsigned integers
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move $t2,$t3
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# $t2 = $t3
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